The proposed study is designed to develop, implement, and assess a culturally competent HIV prevention model for 1200 Mexican-American and Mexican-origin injection drug users (IDUs) in the southeastern region of the Arizona-Sonora border. The study will target the U.S.-Mexico border communities of Douglas-Agua Prieta in Cochise County, Arizona having an estimated cocaine/heroin-using population of 1200, and Nogales-Nogales in Santa Cruz County, having an estimated cocaine/heroin using population of 1500. The specific aims of the study are to: examine and identify patterns of HIV risk in the area; assess the seroprevalence among Mexican-origin IDUs participants; recruit 600 at-risk participants in each site and randomly assign into one of two interventions: a. Those who receive a standard intervention; b. those who receive the culturally competent intervention; through statistical analysis, assess changes in risk behaviors, and AIDS related knowledge, attitudes and perceptions of risk between baseline and follow-up assessments; conduct a thorough formative and process evaluation documenting the development and implementation of the culturally competent model so others in the U.S.-Mexico border area can replicate it if it proves to be successful in changing core components of HIV risk. To accomplish these specific aims, the study proposes a two-staged methodology. The first stage will utilize both quantitative and qualitative approaches to understanding the patterns of HIV risk engagement and possible points of prevention/intervention. In-depth qualitative interviews and focus groups will be used to develop core components of the proposed culturally competent intervention. The second stage of the study will include randomization of eligible participants to one of two community-based interventions--a standard intervention, and a 'culturally competent' intervention designed specifically for the Mexican-origin drug-injecting population targeted.